Connected bar structure



1927. June H. NAGIN CONNECTED B AR STRUCTURE Filed Jan. 28 1926 INJIZENTOR BY 1m 6 A'ITORNEY3 Patented. June 7, 1927.

UNITED STATES 1,631,691 PATENT OFFICE.

HARRY NAGIN, F BROOKLYN, NEW YORK, ASSIGNOB TO THE GRATING COMPANY 01' AMERICA, 0] PITTSBURGH, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA.

CONNECTED BAR STRUCTURE.

Application filed January 28, 1928. Serial No. 84,811.

My invention relates to a new and improved connected bar structure.

One of the objects of my invention is to rovide a structure consisting of a series of 5 ongitudinal bars and a series of cross-bars in which the cross-bars are immovably connected to the longitudinal bars in a simple, reliable and efficient manner, so that the cross-bars are positively locked against no 'movement with respect to said longitudinal bars, in any direction.

Another object of my invention consists 1n making a connected bar structure of this type which is useful for gratings in sidewalks or at other points, for protecting windows and for other purposes, in which the cross-bars are very firmly and reliably connected to the longitudinal bars without the necessity of using rivets.

Other objects of my invention will be set forth in the following description and drawings which illustrate a preferred embodiment of my invention, it being understood that the above statemeint is intended merely to enorally explain the same and not to limit 1t in any manner.

Fig. 1 is a top view. 4 Fig. 2 is a section on the line 2-2 of Fig. 1. Fig.

Fig. 2..

The structure consists of a series of bars 10 which may be called longitudinal bars, and a series of cross-bars 11. The longitudinal bars 10 are provided with recesses 13, each said recess consisting of two or more relatively inclined portions. In the particular embodiment illustrated herein, each recess 13 has two relatively inclined ortions, namely a main or body portion w ich is substantially perpendicular to the edge of 3 is a section on the line 3-3 of the respective bar 10, and aninner inclinedlocking branch.

Each longitudinal bar 10 may have the inclined inner locking branches of the recesses 13 inclined in the same direction. However, each row of recesses in the consecutive bars 10, along a line perpendicular to the respective bars 10, preferably has the respective locking branches thereof inclined in opposite directions. This is illustrated in Fig. 2, because if it is assumed that the front bar 10 has the locking branches of its'recesses inclined towards the right, then the next or the second bar- 10 has said locking branches inclined towards the left, etc. The cross-bars 11 are preferabl unslotted.

After the structure is oosely assembled,

cesses 13. This causes the bottoms of the cross-bars 11 to be bent laterally so as to form lateral portions 12 which fit within the inclined lockmg branches of the recesses 13. I prefer to have the recesses 13 of the same width throughout, and it is not necessary to thicken. or enlarge the bottoms of the crossbars 11 in order to secure a very firm grip between the cross-bars and the longitudinal bars. Since the laterally bent ortions 12 of the cross-bars 11 are alternatey inclined in opposite directions, a very firm hold is so cured.

In order to positively lock the cross-bars 11 from any movement in a direction parallel thereto, I prefer to have each cross-bar 11 of a height or width which is slightly greater than the length of the corresponding recess 13. 3

Hence, when suflicient pressure is applied to force the cross-bars 11 into position, this forces the material at the bottoms of the cross-bars 11 to spread beyond the bottoms of the locking branches of the recesses 13, so that short tongues 14 are thus produced. These tongues 14 are' shown on a very much exaggerated scale in Fi 3. Each crossbar 11 is therefore provi ed with two longitudinal locking tongues 14 which ositively engage the respective longitudinal ar 10.

Hence, the strength of the grip between the various bars does not depend only on a frictional grip, but a positive interlocking 15 secured.

This method of manufacture differs from that in which the cross-bars are initially formed with recesses in the bottom thereof, so that the walls of said recesses can form tongues which grip the longitudinal bars. On the contrary, according to the present invention, the material at the bottoms of the cross-bars is caused to flow or become distorted under the action of the very high pressure utilized, so that the lateral locking tongues 14 are produced either wholly or in (part as the result of said high pressure, an hence these lateral lockin ton ues frictionally grip the longitudinal bars a jacent the bottoms of the recesses 13. The longitudinal bars and the cross-bars are made of any suitable metal.

It would not be departing from my invention if the outer body portions of the slots or recesses 13 would not be perpendicular to the longitudinal edges of the longitudinal bars. The inclined locking branches of the slots 13 could have any desired shape or curvature and could be composed of several portions relatively inclined to each other. Of course, as a matter of manufacturing convenience it is desirable to use ordinary fiat strips of rolled material and to force these into a crooked slot. In the illustrated form of the invention, the slot is crooked at the bottom thereof, it consisting of an upper straight portion and a bottom curved portion.

I have shown a referred embodiment of my invention, but 1t is clear that numerous chan es and omissions could be made without eparting from its spirit.

I claim 2- 1. A connected bar structure comprising a lurality of girder bars having slots formed 1n a side thereof, and cross bars 1 ing in the slots, a slot. in one girder bar eing of a different cross sectional shape than a slot in an adjacent girder bar which is engaged by the same cross bar, the ortions of the cross bar which are engage by the slots being permanently deformed to fit the slots.

2. A connected bar structure comprising a plurality of girder bars having crooked slots formed in the longitudinal edges thereof, the slots being of substantially constant width from top to bottom, and being of different cross sectional shape in different girder bars as Viewed from the same side, and a cross bar having portion-s fitting into the slots, the ortions of the cross bar intermediate the s ots being generally fiat and the portions engaged by the slots being crooked to hold the cross bar in place.

3. A connected bar structure comprising a plurality of girder bars each having slots therein of substantially constant width from top to bottom, the slots at their upper portions being substantially straight and being curved at their lower portions, the lower portions of the slots in different cross bars being inclined in different directions, and a cross bar fitting into the slots, the rtions of the cross bar which are engage b the slots being deformed to correspond wit the slots and hold the cross bar in place.

In testimony whereof I aflix my signature.

HARRY NAGIN. 

